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Baldwin IV

...the burgraveship of Ghent, the land of Waes, and Zeeland. The count of Flanders thus became a feudatory of the empire as well as of the French crown. The French fiefs are known in Flemish history as
Crown Flanders (Kroon-Vlaanderen), the German fiefs as Imperial Flanders (Rijks-Vlaanderen). Baldwin’s son—afterward Baldwin V—rebelled in 1028 against his father at the instigation of...

Flanders

...domain southward to the towns of Douai and Arras and eastward across the Schelde River to Ghent and Antwerp. These counts were vassals of the French king for what they held west of the Schelde (
Crown Flanders, or Kroonvlaanderen, the most important part of the kingdom), and vassals of the German king for what they held east of it (called Imperial Flanders, or Rijksvlaanderen, as part of the...

Robert I

...Ravenshoven, near Kassel, on February 22, 1071, where Robert was victorious. Richilde was taken prisoner, and her eldest son, Arnulf III, was slain. Robert obtained from Philip I the investiture of
Crown Flanders and from Henry IV the fiefs that formed Imperial Flanders.